1. Field of the Invention
The present invention is directed to a system and method for delivery of enhanced directory assistance. More particularly, the present invention relates to a system and method for delivery of enhanced directory assistance, utilizing a cross protocol universal call identifier.
2. Description of the Related Art
Enhanced directory assistance systems are used to provide directory assistance (DA) to callers, responding to requests for all types of information including telephone numbers, directions and reservation services. The directory assistance systems currently employed typically employ a number of network elements. Network elements refer to the physical devices within the directory assistance system used to carry out various functions, including internal routing of the calls, interfacing with operators, call completion, data storage, and other such functions.
Examples of network equipment used in directory assistance systems include but are not limited to Lucent 5ESS (network switch), Nortel DMS (voice circuit switches), Cisco Devices AS5400, 6500, 7200, PGW, GSR (eg. network routers), Soft switches (Telica Plexus, Sonus), Session Border Controllers and LAN/WAN switches. Most of these network elements in directory assistance systems may support a number of different protocols used for such tasks as call setup or billing.
A universal call identifier (UCI) is used to track calls within a particular operating protocol. These UCIs are present in most protocols such as Signaling System 7 (SS7) and Session Initiation Protocol (SIP). However, currently UCIs only operate within a single protocol. This is because UCI comes in various lengths and formats, and are thus not portable between protocols.
For example, a directory assistance call to an enhanced directory assistance system may first enter the system via a first network switch using the SS7 protocol, it is then assigned a transaction ID, referred to as a UCI. Within the same network of the directory assistance system, the call could then be transported to another switch using Inter-Machine Trunks (IMT) with the Primary Rate Interface (PRI) protocol, which uses a different UCI than the one provided by the SS7 protocol. From there, the same call could then be sent out of the system to the caller using the SIP protocol, again using a different UCI. In this example, each of the protocols utilize a different UCI. The different UCIs are not related to one another and they are not transferable outside one network element, to other network elements that use different protocols.
Such an arrangement presents problems with troubleshooting individual calls within the directory assistance system, because the system's network uses different network equipment for different functions, each of which may be operating on different protocols. Because of this, system administrators can not easily perform disambiguation of individual calls and connecting of call legs together, when attempting to trace a call pathway through the DA system. Additionally, the different protocols, each using different UCIs, make bill reclamation difficult because the point of call failure can not easily be traced, again because the call legs within the network are difficult to piece together.